The present invention is directed to millimeter-wave and microwave circuit oscillators.
Millimeter-wave/microwave transceiver technology is useful in numerous applications, including vehicle obstacle avoidance and smart munitions applications. Transceiver radars operating within this wavelength range can penetrate fog and smoke, and provide good detection target resolution. Vehicle obstacle avoidance and smart munitions applications require highly efficient transceivers that are low in cost. To achieve high-efficiency, high Q-factor oscillator sources must be used which must be low in cost and provide good frequency stability and low noise output.
Traditionally, two types of oscillator sources have been used in millimeter-wave/microwave transceivers, referred to as integrated oscillators and waveguide cavity-based oscillators. Some integrated oscillators, such as transistor-based integrated oscillators, use costly components and are, therefore, too expensive. Other integrated oscillators, such as microstrip or coplanar integrated oscillators, use dielectric material and highly resistive elements and therefore do not exhibit high Q-factor operation. Waveguide cavity-based oscillators are also undesirable because they are often bulky, require highly labor-intensive post-assembly tuning and testing, and are not adaptable to low-cost batch fabrication methods, making them too expensive for use in most applications.
Therefore, there is a need for a high Q-factor oscillator that can be produced at an affordable cost and can be used in the millimeter-wave/microwave wavelength range.